1. Technical Field
The present invention relates to a liquid ejecting head for ejecting liquid, through a nozzle, that has been introduced into a pressure chamber through a flow path provided inside the liquid ejecting head, and a liquid ejecting apparatus that includes the stated liquid ejecting head.
2. Related Art
Liquid ejecting apparatuses are an apparatus that includes a liquid ejecting head and ejects various types of liquids from the liquid ejecting head. As the liquid ejecting apparatuses, for example, image recording apparatuses such as an ink jet printer, an ink jet plotter, and the like can be cited. In addition, nowadays liquid ejecting apparatuses are also applied in various types of manufacturing apparatuses because the liquid ejecting apparatuses can precisely land a minute amount of liquid onto a predetermined position. For example, they are applied in display manufacturing apparatuses for the manufacture of color filters of liquid crystal displays or the like, electrode forming apparatuses for the formation of electrodes of organic EL (electroluminescence) displays, FEDs (surface emitting displays) or the like, and chip manufacturing apparatuses for the manufacture of biochips (biochemical elements). A recording head of an image recording apparatus ejects ink in liquid form, and a coloring material ejecting head of a display manufacturing apparatus ejects solutions of different coloring materials of R (red), G (green) and B (blue). Further, an electrode material ejecting head of an electrode forming apparatus ejects an electrode material in liquid form, and a bioorganic matter ejecting head of a chip manufacturing apparatus ejects a solution of bioorganic matter.
The liquid ejecting heads mentioned above are configured so that liquid is introduced into a pressure chamber from a cartridge in which the liquid is stored, a pressure change in the liquid inside the pressure chamber is generated, and then the liquid is ejected through a nozzle communicating with the pressure chamber. Such liquid ejecting head is structured of a plurality of laminated members, in which the cartridge communicates with the pressure chamber via a plurality of passages provided inside the laminated members. Note that a seal member made of an elastic material is used so as to make the passages in the laminated members communicate with each other in some case.
For example, JP-A-2003-39672 discloses a configuration in which a main head body having a head flow path to communicate with a nozzle and a head holder having a holder flow path formed therein to introduce ink from an ink cartridge to the head flow path are included, and in which the holder flow path and the head flow path are made to communicate with each other by a seal member disposed between the main head body and the head holder. To be more specific, the seal member is nipped and pressed down to deform between an opening edge of the head flow path and an opening edge of the holder flow path so that the head flow path and the holder flow path are made to communicate with each other via a communication port provided in the seal member.
However, in the liquid ejecting head described above, reactive force is produced in a portion of the seal member that is nipped and pressed down to deform and stress caused by the reactive force is transmitted to the members on the upper and lower sides of the seal member and also to other members, which raises a risk that the whole liquid ejecting head is deformed. If the liquid ejecting head is deformed, there is a risk that an ejection (discharge) failure occurs in which a landing position of a liquid droplet ejected through the nozzle is deviated from a desired position, or the like. Meanwhile, although it can be considered to reduce the reactive force by lessening the force of nipping and pressing down to deform the seal member, there is a risk that a sealing effect is lowered between the flow paths communicating with each other by the seal member. In the case where the seal member is not sufficiently nipped and pressed down to deform, an inner surface of the communication port of the seal member is not flush with an inner surface of the flow path so that a step is produced therebetween. If such step is produced, air bubbles stay at the step when liquid is injected, which raises a risk of the occurrence of the ejection failure.